JP2620874B2 - Control device for hydraulically operated transmission for vehicles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a control device for a hydraulically operated transmission for a vehicle mainly used for an automobile.

(Prior Art) Conventionally, as seen in JP-A-61-84450, etc.,
A hydraulically actuated shift for vehicles comprising a four-speed transmission system for forward movement established by separate hydraulic clutches, and interposing a one-way clutch that allows overspeed on the output side to the first-speed transmission system at the lowest speed. A hydraulic circuit including a manual valve that can be switched between an automatic shift range and a low-speed holding range, a first to third shift valves that can be switched between a shift-down position and a shift-up position, When the manual valve is switched to the automatic shift range, only the first-speed hydraulic clutch that establishes the first-speed transmission system is supplied with oil at the downshift position of the first shift valve, and the first shift valve is switched to the upshift position. The second shift valve is refueled through the first shift valve, and the second shift valve is switched to a downshift position to refuel a second speed hydraulic clutch that establishes a second speed transmission system. A third-speed hydraulic clutch and a fourth-speed transmission that supply oil to the third shift valve by switching to the shift-up position and establish a third-speed transmission system by switching the third shift valve between the downshift position and the upshift position. The four-speed transmission system that establishes the system is selectively lubricated, and the shift valves are switched to perform first- to fourth-speed automatic shifting. In the low-speed holding range of the manual valve, the shift valve is not interposed. It is known to supply oil to a second-speed hydraulic clutch to establish a second-speed transmission system.

(Problems to be Solved by the Invention) When a one-way clutch is interposed in the first-speed transmission system as described above, the engine brake is not effective in the first-speed transmission system. Therefore, a one-speed hold hydraulic clutch is provided in parallel with the one-way clutch. By transmitting the reverse drive torque via the hydraulic clutch, the engine brake can be activated even in the first-speed transmission system. In the low-speed holding range of the manual valve, the first-speed hydraulic clutch is always supplied with oil, and the first-speed hold hydraulic clutch is connected. It has been considered to selectively supply oil to the second-speed hydraulic clutch so that the first-speed transmission system and the second-speed transmission system can be selectively established.

In this case, if a dedicated shift valve for selectively refueling the first-speed hold hydraulic clutch and the second-speed hydraulic clutch is provided, the structure becomes complicated. It is desired to also use a shift valve for shifting.

The object of the present invention is to provide a device that meets such needs.

(Means for Solving the Problems) In order to achieve the above object, according to the present invention, there are provided at least three forward drive transmission systems established by respective hydraulic clutches, and a first speed drive system at the lowest speed stage. An automatic transmission range and a low-speed holding range are provided in a hydraulic circuit of a vehicle hydraulically operated transmission including a one-way clutch that allows over-rotation on the output side and a first-speed hold hydraulic clutch in parallel with the one-way clutch. A manual valve that can be switched and a first and second at least two shift valves that can be switched between a shift-down position and a shift-up position, and a first oil passage extending from the manual valve to the second shift valve Intervening the first shift valve to communicate the first oil passage at the shift-up position of the first shift valve, and cut off the communication of the first oil passage at the shift-down position of the first shift valve. And then A second oil passage connected to a second-speed hydraulic clutch that establishes a second-speed transmission system is connected to the first oil passage at a shift-down position of the second shift valve, and an up-shift position of the second shift valve is connected; The second oil passage is connected to the third oil passage, and when the manual valve is switched to the automatic transmission range, the first oil passage is connected to a hydraulic source via a manual valve, In the downshift position of the first shift valve, oil is supplied only to the first-speed hydraulic clutch that establishes the first-speed transmission system, which is arranged in series with the one-way clutch. By switching the valve to the downshift position, the first oil passage is supplied to the second-speed hydraulic clutch via the second oil passage, and the second shift valve is switched to the shift-up position by the second-speed transmission system. When lubricating the hydraulic clutch that establishes the transmission system of the high-speed stage, In those adapted to discharge oil from the second-speed hydraulic clutch via the oil passage of the second oil passage and the third,
The third oil passage is connected to an oil discharge passage via the manual valve in an automatic speed change range of the manual valve, and in a low-speed holding range of the manual valve, a first-speed hydraulic clutch is constantly supplied with oil and the first oil is supplied. The oil supply to the passage is cut off, the third oil passage is switched from the drain oil passage to the hydraulic pressure source, and the third oil passage is switched by switching the second shift valve to a downshift position. A fourth oil passage connected to the
The fourth oil passage was connected to the first-speed hold hydraulic clutch.

In this case, it is preferable that a branch path connected to the oil discharge port of the manual valve be provided in the fourth oil path in the automatic transmission range of the manual valve.

(Operation) In the automatic shift range of the manual valve, the second shift valve is switched to the upshift position to drain the oil from the second speed hydraulic clutch via the second oil passage, the third oil passage, and the drain oil passage. However, in the low-speed holding range, since the third oil passage is connected to the hydraulic pressure source, the second shift valve is switched to the shift-up position through the third oil passage → the second oil passage. The second-speed hydraulic clutch is supplied with oil to establish a second-speed transmission system, and according to the switching of the second shift valve to the downshift position, the fourth oil passage is connected to the third oil passage. The first-speed hold hydraulic clutch is supplied with oil, while the second oil passage is connected to the first oil passage, but is not supplied to the first oil passage, so that the second-speed hydraulic clutch is disengaged, The one-way clutch is switched by the first-speed hydraulic clutch and the first-speed hold hydraulic clutch that are constantly refueled. Scan the system path in the first speed transmission train is established, so that The vehicle is able to run at the first speed transmission system in which engine brake.

By the way, if the manual valve is switched to the automatic transmission range during traveling in the first speed transmission system in the low speed holding range, and the traveling state at the time of the operation falls within the second speed region of the shifting characteristics in the automatic transmission range, Since the second shift valve is held in the shift down position, the second-speed hydraulic clutch is supplied with oil through the first oil passage and the second oil passage at the same time as the manual valve switching operation, and is switched from the first-speed hold hydraulic clutch. If the first-gear transmission system and the second-gear transmission system co-mesh with each other, a shift shock occurs.

Here, oil is drained from the first-speed hold hydraulic clutch via a fourth oil passage, a third oil passage, and an oil discharge passage. An oil passage for draining oil from the second-speed hydraulic clutch at the time of shift-up, and an orifice intervening to suppress engine blow-up due to a sudden drop in pressure of the second-speed hydraulic clutch at the time of shift-up. When the oil is drained through the oil drain, the co-meshing state occurs as described above.

In this case, if a branch path communicating with the oil discharge port of the manual valve in the automatic transmission range of the manual valve is provided in the fourth oil path,
The oil from the first-speed hold hydraulic clutch is directly drained from the manual valve via the branch to the fourth oil passage, and the engagement force of the hydraulic clutch is quickly reduced, thereby preventing the occurrence of the co-meshing state. .

(Embodiment) Referring to FIG. 1, (1) shows a transmission that performs four forward speeds and one reverse speed, and the transmission (1) is connected to an engine via a fluid torque converter (2). Input shaft (1
a) a first to fourth speed transmission system (G1), (G2), (G3), (G4) for forward movement between a) and an output shaft (1b) connected to a driving wheel of the vehicle via a differential gear (3). ) And a reverse transmission system (GR), and each of the forward transmission systems (G1) (G2) (G3) (G4) has a first to fourth speed hydraulic clutch (C1) (C
2) (C3) (C4) intervening, each hydraulic clutch (C1)
(C2) (C3) (C4) engages each transmission system (G1) (G
2) Selectively establish (G3) and (G4), and use the 4-speed transmission system (G4) and the 4-speed hydraulic clutch (C4) on the input shaft (1a) for the reverse transmission system (GR). The two transmission systems (G4) and (GR) are switched by the operation of switching the selector gear (4) on the output shaft (1b) between the left forward side and the right reverse side in the drawing. (4) is selectively established by meshing with the driven gears (G4a) (GRa) of the transmission systems (G4) (GR).

In the first-speed transmission system (G1), a one-way clutch (5) that allows overspeed on the output side is interposed.
A first gear meshing with a drive gear (G1a) of the first-speed transmission system (G1) on an intermediate shaft (6) provided so as to straddle the arrangement of the first transmission system (G1) and the fourth-speed transmission system (G4); ₍₇₁₎ as well as fixed and fourth speed transmission train (G4) drive gear rotatably supports the second gear that meshes with the (G4b) (7 _2), the first gear (7 ₁₎ the first speed transmission system an equal diameter driven gear and (G1b) of (G1), also formed at equal diameter and driven gear (G4a) of the second gear (7 ₂₎ of the fourth speed transmission train (G4), these first gear (7 ₁ ), the second gear (7 ₂ ), and the fourth speed transmission system (G4) constituted a bypass path parallel to the one-way clutch (5). Then, to connect the second gear on the intermediate shaft (6) (7 ₂₎ on the shaft (6) 1
A first-speed transmission system (G1) can be established with a one-way clutch (5) bypassed by providing a high-speed hold hydraulic clutch (CH) and engaging the hydraulic clutch (CH) and the first-speed hydraulic clutch (C1). I did it.

Each hydraulic clutch (C1) (C2) (C3) (C4) (CH)
Is controlled by a hydraulic circuit shown in FIG. 2. The hydraulic circuit includes a hydraulic power source (8) and a parking range as shown in FIG. There are a total of 6 ranges: "P" for barrel, "R" for reverse range, "N" for neutral range, "D" and "S" for automatic shift, and "2" for low speed hold. A manual valve (9) capable of switching operation, a first shift valve (10 ₁ ) for first-speed / second-speed switching, and a second shift valve for second-speed / third-speed switching
Forward / reverse switching in which the shift valve (10 ₂ ), the third shift valve (10 ₃ ) for switching between the third and fourth speeds, and the selector gear (4) are connected via a fork (4a) engaged with the selector gear (4) In the "D" range of the manual valve (9), a first oil passage (L1) for oil supply connected to the hydraulic pressure source (8) is provided with an annular groove (11) of the valve (9). 9a) via the first shift valve (10 ₁ )
The second oil passage (L2) connecting to the second oil passage (L2)
4) and the first oil passage (L1) to the second oil passage (L2)
The pressure oil adjusted to a constant line pressure by the regulator valve (12) is supplied to the oil passage (L14) and the fourteenth oil passage (L14).
4) Supplying oil to the first-speed hydraulic clutch (C1) via the third oil passage (L3) connected to the first oil passage (L3), and supplying the first to third oil from the second oil passage (L2).
The second to fourth speed hydraulic clutches (C2), (C3), and (C4) are supplied with oil via shift valves (10 ₁ ) (10 ₂ ) (10 ₃ ).

The first shift valve (10 ₁ ) is switchable between a right first speed position as a downshift position and a left second speed position as an upshift position, and the second shift valve (10 ₂ ) is a right shift down position. The third shift valve (10 ₃ ) is capable of switching between the second gear position and the left third gear position which is an upshift position. And a modulator position (a constant pressure lower than the line pressure) from a modulator valve (13) connected to the first oil passage (L1). An oil chamber at the right end of the first shift valve (10 ₁ ) and the second shift valve (10 ₂ ) through a fifth oil path (L5) connected to the fourth oil path (L4) through an orifice (14 ₁ ). 10 ₁ a) (10 ₂ a)
The left end oil chamber (10 ₁ b) of the first shift valve (10 ₁ ) is connected to the third oil passage (10 ₁ b) via a sixth oil passage (L 6) connected to the fourth oil passage (L 4) via another orifice (14 ₂ ). The oil chamber (1 on the right end of the shift valve (10 ₃ )
0 ₃ a) and be input to, fifth oil passage (L5) electromagnetically normally closed first air release valve (15 _1), the sixth oil passage (L
6) is connected to an electromagnetic normally-closed second air release valve (15 ₂ ), and these shift valves (10 ₁ ) (10 ₂ ) are opened and closed by opening and closing both air release valves (15 ₁ ) (15 ₂ ). ) (10 ₃ ) is changed as follows in accordance with each shift speed.

That is, in the first speed stage, the first atmosphere release valve (15 ₁ ) is opened and the second atmosphere release valve (15 ₂ ) is closed. According to this, the first second shift valve (10 ₁ ) ( 10 ₂ ) Rightmost oil chamber (10 ₁ a)
The input of the modulator pressure to (10 ₂ a) is cut off, and the oil chamber (10 ₁ b) at the left end of the first shift valve (10 ₁ ) and the third shift valve (1
0 ₃ ), the modulator pressure is input to the rightmost oil chamber (10 ₃ a), and the first shift valve (10 ₁ ) is shifted to the right first speed position against the rightmost spring (10 ₁ c). The second shift valve (10 ₂ ) is biased by the left end spring (10 ₂ c) to the right second speed position, and the third shift valve (10 ₃ ) is opposed to the left end spring (10 ₃ c). The operation is switched to the left fourth speed position. In this state, the first shift valve (10
₁ ) the second oil passage (L2) on the inflow side and the second shift valve (1).
0 ₂ ), the communication with the outflow-side seventh oil passage (L7) is cut off,
Oil is supplied only to the first-speed hydraulic clutch (C1) via the fourteenth oil passage (L14) and the third oil passage (L3), and the first-speed transmission system (G1) is established.

In the second speed, the first and second atmosphere release valves (15 ₁ ) and (15 ₂ ) are both opened, and according to this, the first shift valve (10 ₁ )
The input of the modulator pressure to the leftmost oil chamber (10 ₁ b) of the third shift valve (10 ₃ ) and the rightmost oil chamber (10 ₃ a) of the third shift valve (10 ₃ ) is also cut off, and the first shift valve (10 ₁ ) The 3 shift valve (10 ₃ ) and the 2nd shift position on the left and the 3rd shift on the right are biased by the springs (10 ₁ c) and (10 ₃ c), respectively.
The operation is switched to the second speed position, and the second shift valve (10 ₂ ) is held at the second speed position in the same manner as described above. In this state, the second oil passage (L2) is connected to the seventh oil passage (L7) via the annular groove (10 ₁ d) of the first shift valve (10 ₁ ), and the seventh oil passage (L7) At the second speed position of the second shift valve (10 ₂ ) via an eighth oil passage (L8) connected via an annular groove (10 ₂ d) of the valve (10 ₂ ).
Oil is supplied to the high-speed hydraulic clutch (C2), and the second-speed transmission system (G2) is established. In this case, the one-way clutch (5)
The power transmission via the first-speed transmission system (G1) is automatically stopped by the action of.

At the third speed, the first air release valve (15 ₁ ) is closed and the second air release valve (15 ₂ ) is opened. According to this, the first and second shift valves (10 ₁ ) (10 ₂ ) are opened. ) The rightmost oil chamber (10 ₁ a) (10
₂ a) the modulator pressure is inputted to the second shift valve (1
0 ₂ ) is switched to the left third speed position against the spring (10 ₂ c), and the first shift valve (10 ₁ ) and the third shift valve (10 ₃ ) are shifted to the second speed position and the third speed position, respectively. Held in position. In this state, the seventh oil passage (L7) is connected to the annular groove (10 ₂ e) of the second shift valve (10 ₂ ).
Oil passage (L10) connected to the third shift valve (10 ₃ ) via
At the third speed position of the third shift valve (10 ₃ ).
0 ₃ ) through the eleventh oil passage (L11) connected to the tenth oil passage (L10) through the annular groove (10 ₃ d).
The third oil passage (L8) connected to the second-speed hydraulic clutch (C2) is refilled with the eighth groove (10 ₂ ) of the second shift valve (10 ₂ ).
d) through the notch groove (9b) of the valve (9) in the "D" range of the manual valve (9) to the ninth oil passage (L9). First drainage line (LD1) to be connected
The oil is drained from the second-speed hydraulic clutch (C2) via the third gear, and the third-speed transmission system (G3) is established.

In the fourth speed, the first and second atmosphere release valves (15 ₁ ) and (15 ₂ ) are both closed. According to this, the first shift valve (10 ₁ )
And the second shift valve (10 ₂ ) are held at the second speed position and the third speed position, respectively, as in the case of the third speed stage, and the third shift valve (10 ₃ ) controls the modulator pressure to the rightmost oil chamber (10 ₃ a). Is switched to the left fourth speed position. The first shift valve (10 _1), the pressing force balance between the left and right by the modulator pressure by inputting Mojiyureta pressure of the oil chamber at both ends to the (10 ₁ a) (10 ₁ b), The second speed position is maintained by the urging force of the spring (10 ₁ c). In this state, the tenth oil passage (L10)
Through the annular groove (10 ₃ e) of the shift valve (10 ₃ ), the twelfth oil passage (L
The thirteenth oil passage (L13) connected to the twelfth oil passage (L12) through the notch groove (9c) of the valve (9) in the "D" range of the manual valve (9). And the eleventh oil passage (L11) connected to the third-speed hydraulic clutch (C3) passes through the annular groove (10 ₃ d) of the third shift valve (10 ₃ ). The oil is drained from the third-speed hydraulic clutch (C3) by being connected to the second oil passage (LD2) via the second oil passage (LD2), and the fourth-speed transmission system (G4) is established.

When shifting down from 4th gear to 3rd gear, the twelfth oil passage (L1
2) is connected to the third oil discharge passage (LD3) via the annular groove (10 ₃ e) of the third shift valve (10 ₃ ) located at the third speed position, and oil is drained from the fourth speed hydraulic clutch (C4). Is performed, and at the time of downshifting from third gear to second gear, it is connected to the eleventh oil passage (L11) via the annular groove (10 ₃ d) of the third shift valve (10 ₃ ) located at the third gear position. that No. 10 oil passage (L10) via the annular groove (10 ₂ e) of the second shift valve existing in second speed position (10 ₂₎ fourth oil discharge passage (LD
4), the oil is drained from the third-speed hydraulic clutch (C3), and when downshifting from second gear to first gear, it is connected to the second oil passage (L2) as described above in the second gear. 7th oilway (L
7) is a switching operation of the first shift valve (10 ₁ ) to the first speed position, and through the annular groove (10 ₁ d) of the valve (10 ₁ ), the oil discharge port (10 ₁ ).
Is connected to the ₁ e), where because it is connected to said 7 oil passage (L7) the eighth oil passage like the second speed (L8) through the second speed hydraulic clutch (C2), these oils Oil is discharged from the second-speed hydraulic clutch (C2) via the roads (L8) and (L7).

More as the manual valve (9) in the "D" range, the first second air release valve (15 ₁₎ (15 ₂₎ opened and closed by first speed through the fourth-speed transmission train of (G1) (G2) (G3) (G4) is selectively established, and a signal from an engine throttle opening sensor (16a) (such as an intake pipe negative pressure related to the engine load, etc.) is sent to an electronic control circuit (16) comprising a microcomputer as shown in FIG. Other signals may be used), a signal from a vehicle speed sensor (16b), and a position sensor (16) of a manual valve (9).
c) and the first-speed hold switch (16
d) and the control circuit (16) connects the two air release valves (15 ₁ ) and (15 ₂ ) to their solenoids (15a) so that the shift characteristics as shown in FIG. 5, for example, can be obtained. Opening / closing is controlled by turning on and off the power.

In the drawing, (A1) (A2) (A3) (A4) (AH) are used to buffer sudden pressure changes during oil supply / discharge of each hydraulic clutch (C1) (C2) (C3) (C4) (CH) Accumulator provided,
(17) regulates the line pressure input from the fourteenth oil passage (L14) connected to the first oil passage (L1) via the manual valve (9) to a throttle pressure corresponding to the throttle opening and outputs the adjusted pressure. A throttle valve from the throttle valve (17), and accumulators (A1) (A1) for the first to fourth speeds.
2) A back pressure is applied to (A3) and (A4), and a pressure reducing valve (18) pressed to the right opening side by the throttle pressure is interposed in the second oil passage (L2) to reduce the throttle opening. In the low opening region, the supply pressure to the downstream side of the second oil passage (L2) is reduced. Incidentally, the pressure reducing valve (18) is known in JP-A-59-166750, and a detailed description thereof will be omitted.

Wherein each oil discharge passage (LD1) (LD2) (LD3) (LD4), respectively drain oil control valve (19 ₁₎ (19 ₂₎ (19 ₃₎ (19 ₄₎ and this parallel orifices (20 ₁ ) (20 ₂ ) (20 ₃ ) (20 ₄ ) intervening, and each of the control valves (19 ₁ ) (19 ₂ ) (19 ₃ ) (19 ₄ ) is closed and opened to discharge each oil. It was made possible to control increase / decrease of the line resistance of the road (LD1) (LD2) (LD3) (LD4).

To explain this in more detail, the second oil discharge passage (LD) connected to the third speed hydraulic clutch (C3) at the time of upshifting from third speed to fourth speed
The second oil discharge control valve (19 ₂ ) interposed in ₂ ) is pressed to the left open side by the hydraulic pressure (hereinafter referred to as the 4th pressure) of the 4th speed hydraulic clutch (C4) on the engagement side, and 4th gear shift up to 4th gear
Rise to a predetermined pressure of speed pressure the control valve (19 ₂₎ is opened, the
Before and after that, the pressure drop characteristics of the hydraulic pressure of the disengaged third speed hydraulic clutch (C3) (hereinafter referred to as the third speed pressure) differed more or less.
The release timing of the high-speed hydraulic clutch (C3) is appropriately controlled, so that a smooth shift can be obtained without causing engine stall due to engine blow-up or unnecessarily co-engaging. In addition, the third oil discharge passage (LD) connected to the fourth-speed hydraulic clutch (C4) when downshifting from fourth-speed to third-speed
The third oil discharge control valve (193) interposed in ₃ ) is pressed to the left opening side at the third speed pressure on the engagement side and is opened at the third pressure increase, and is opened from the fourth speed to the third speed. In the same manner as described above. By the way, the shift characteristics may be set such that the shift is performed between the second speed and the fourth speed while skipping the third speed in running conditions, for example, in a case of a sudden accelerator operation or the like. The first corresponding to C2)
The first oil drain control valve (19 ₁ ) interposed in the oil drain (Ld1)
As disclosed in Japanese Patent Application Laid-Open No. 61-84450, the right and left shifts are established at the third and fourth speeds so as to be able to cope with both the speed-up shift of the third speed and the shift-up of the second speed to the fourth speed. Side and the control valve (19 ₁ ) is connected to the second speed hydraulic clutch (C
2) The hydraulic pressure (hereinafter referred to as the 2nd pressure) is pressed to the left closing side, and when the upshift of 2nd → 3rd and 2nd → 4th is performed, the 2nd pressure of the release side drops and the The valve is opened when the pressure difference between the third speed and the fourth speed is reduced to a predetermined value or less. Incidentally, such a differential pressure responsive type oil control valve is disclosed in Japanese Patent Application Laid-Open No. 61-82.
It is known from 051.

Also, at the time of downshifting from third speed to second speed, the fourth oil passage (LD4) connected to the third speed hydraulic clutch (C3)
As the oil discharge control valve (19 ₄₎ is assumed to be pressed toward the leftward open position by second speed pressure of the engagement side, it may also address the downshift further fourth speed → 2-speed, 4-speed hydraulic clutch ( wherein connected to C4) third oil discharge passage (LD3) the control valve (19 ₄₎ third oil discharge connected via a branch channel (light LDs 3a) to a common inlet port (19 ₄ a) of The control valve (19 ₄ ) is interposed in the road (LD3) in parallel with the _third oil discharge control valve (193 ₃ ) so that the second side pressure on the engagement side can be maintained even when downshifting from fourth to second speed. The 4th speed pressure on the release side was quickly lowered by ascending. In this case, 3rd gear →
When second speed shift down, through the inlet port (19 ₄ a) and the third oil discharge passage (LD3) from the fourth oil discharge passage (LD4) before the opening of the fourth oil discharge control valve (19 ₄₎ The oil in the third-speed hydraulic clutch (C3) is discharged from the orifice (20 ₃ ), and the drop in the third-speed pressure is steeper than the pressure-reducing characteristic specified by the orifice (20 ₄ ) in the fourth oil discharge passage (LD4). 4th fork (LD3a) to avoid
Check valve (21 ₁ ) to prevent backflow of oil from the oil drain (LD4)
And the fourth oil drain (LD4) is also connected to the third oil drain (L4).
A check valve (21 ₂ ) for preventing the backflow of oil from D3) is provided.

Also, when downshifting in the low opening region of the throttle opening, smoother gear shifting is performed by rapidly lowering the clutch pressure on the release side, and as described in JP-A-61-227956, the third third oil discharge control valve (19 ₃₎ and the fifth oil discharge control valve is opened at a low throttle opening in parallel to the oil discharge passage (LD3) and (19 _5), the fourth oil discharge passage (LD4 sixth) is opened at a low throttle opening in parallel with the fourth oil discharge control valve (19 ₄₎
Oil discharge control valve and (19 ₆₎ were each interposed, wherein said 6 oil discharge control valve (19 ₆₎ is constituted by a plunger which presses the throttle valve (17), in conjunction with the throttle opening shall be pushed to the closing side of the left by the operating element (19 ₆ a) that, push the closing side of the left by a throttle pressure from the fifth oil discharge control valve (19 ₅₎ is a throttle valve (17) shall be dynamic, low throttle opening respective control valve (19 ₅₎ (19 ₆₎ is returned to the opening of the right position, the third speed → 2-speed, 4-speed → 3-speed, 4-speed → 2 3 speed pressure and the fourth speed pressure during downshifting speed is to be quickly lowered at oil discharge through the respective control valve (19 ₅₎ (19 _6).

Further, if the downshift third speed → 1 speed has been performed, the second oil discharge control valve interposed in No. 2 oil discharge passage (LD2) connected to the third speed hydraulic clutch (C3) (19 ₂₎ is If the valve is not opened, the oil is drained only from the orifice (20 ₂ ),
The speed drop slows down and the accelerator pedal is depressed.
It takes time until the first-speed transmission system (G1) is established during the kickdown shift from the first speed to the first speed, resulting in poor acceleration. Therefore, the second oil drain passage (LD2) is connected to the first shift valve (10 ₁ ).
At the high speed position, the oil is connected to the oil discharge port (10 ₁ g) through the annular groove (10 ₁ f) formed in the valve (10 ₁ ). The first-speed transmission system (G1) can be established without a time lag by draining oil from the oil drain port (10 ₁ g). still,
In the "D" range of the manual valve (9), the first-speed hydraulic clutch (C1) is always engaged, and the third-speed hydraulic clutch (C3)
When the is released, the first speed transmission system (G1) is established.

Moreover, said the fourth speed of the accumulator (A4) so as to enter the throttle pressure through the third shift valve (10 _3), said accumulator (A4 in third speed position of the third shift valve (10 ₃₎ ) The back pressure chamber with the annular groove (10 ₃ f) of the valve (10 ₃ )
To the oil drain port (10 ₃ g) to change the accumulator characteristics between upshift and downshift.

The oil passage configuration in the "D" range of the manual valve (9) has been described above. However, the oil passage configuration in the "S" range is the same as that in the "D" range, and the first and second atmosphere release valves (15 ₁ ) (1
5 ₂₎ by switching the speed change characteristics stored in the electronic control circuit (16) for opening and closing, and performs automatic speed changing of the first speed through the fourth speed in such transmission characteristics shown in example Figure 6. The shift characteristics in FIG. 6 are set so that the shift is performed at a higher speed than that in FIG. 5, and is suitable for sporty running or mountain running.

In the "2" range of the manual valve (9), the second oil passage (L
2) through the cutout groove (9d) of the valve (9)
e), and a branch passage (L7a) branched from the seventh oil passage (L7) passes through a radial communication hole (9f) formed in the manual valve (9) to form a shaft of the valve (9). A fourteenth oil passage (L14) connected to the oil drain port (9g) formed of a hole and connected to the first oil passage (L1) through the cutout groove (9h) of the manual valve (9) is connected to the valve ( The ninth oil passage (L9) is connected to the ninth oil passage (L9) through the annular groove (9i) of 9), and the second shift valve (10 ₂ ) is supplied with oil through the ninth oil passage (L9).

When the second shift valve (10 ₂ ) is switched to the second speed position, the annular groove (1 ₂ ) of the valve (10 ₂ ) is inserted into the ninth oil passage (L9).
0 ₂ f), a fifteenth oil passage (L15) connected through
1st-speed hold hydraulic clutch (CH) in 15 oil passages (L15)
Connected.

In the "2" range, the first-speed hydraulic clutch (C1) is constantly supplied with oil from the fourteenth oil passage (L14) via the third oil passage (L3). When the air release valves (15 ₁ ) and (15 ₂ ) are both opened (the state of the second gear in the “D” and “S” ranges) and the second shift valve (10 ₂ ) is switched to the second gear position, The first-speed hold hydraulic clutch (CH) is supplied with oil via the oil passage (L9) and the fifteenth oil passage (L15), and the first-speed transmission system (G1) is established with the one-way clutch (5) bypassed. The first speed transmission system (G1) enables the vehicle to travel with the engine brake applied, and the first air release valve (15 ₁ ) is closed and the second air release valve (15 ₂ ) is opened (“D When the second shift valve (10 ₂ ) is switched to the third speed position, the ninth oil passage (L9) becomes the eighth oil passage (L8) as described above. To the second speed hydraulic clutch (C2) and the 15th oil passage (L15)
Shift valve (10 ₂ ) through annular groove (10 ₂ f) of said valve (10 ₂ )
Connected to the oil drain port (10 ₂ g) of the first-speed hold hydraulic clutch (CH), and the second-speed transmission system (G2)
Is established. In the second speed position of the second shift valve (10 ₂ ), the eighth oil passage (L8) is connected to the seventh oil passage (L7), and the oil from the second speed hydraulic clutch (C2) is connected to the branch passage (L7a). ) Through the oil drain port (9g) of the manual valve (9).

The shift characteristics in the "2" range can be switched by operating the first speed hold switch (16d).
When the switch (16d) is turned off, the first-speed and second-speed shifting is performed according to the characteristic shown by the line a in FIG. 7, and when the switch (16d) is turned on, the first-speed transmission system ( G
1) To keep established. The switch (16d)
When the vehicle is running at a speed higher than the b-line at the time of turning on, the second speed transmission system (G2) is first established to prevent the engine from overrunning, and when the vehicle speed becomes lower than the b-line, the first speed is established. The transmission system (G1) was established, and was kept at 1st gear thereafter.

By the way, during the first speed running in the "2" range, "D"
When switching to the "S" range, the driving state becomes "D""S"
If the vehicle is in the second speed range of the shift characteristics in the range,
Since the shift valve (10 ₂ ) is held at the second speed position, the second speed hydraulic clutch (C2) is immediately supplied with oil from the seventh oil passage (L7) via the eighth oil passage (L8). hold oil hydraulic clutch (CH), which is discharged from No. 15 oil passage (L15) and the ninth oil passage (L9) first oil discharge passage via the (LD1), exhaust oil passage (LD ₁ ) for the orifice (20 ₁₎ is intervention in oil discharge of the first-speed holding hydraulic clutch (CH) is delayed, resulting chewing co the first speed transmission train and (G1) 2 speed transmission system and (G2) The shift shock occurs.

Therefore, in the present embodiment, a branch path (L15a) branched from the fifteenth oil path (L15) is provided, and in the "D" and "S" ranges, the branch path (L15a) is connected to the communication hole (9f) of the manual valve (9). ) Is connected to the oil discharge port (9g) to speed up the oil discharge from the first-speed hold hydraulic clutch (CH) so as to suppress co-meshing. Note that even if the first-speed hold hydraulic clutch (CH) is released before the second-speed hydraulic clutch (C2) is engaged, the first-speed hydraulic clutch (C1) is engaged, so that the first-speed hydraulic clutch (C1) is engaged via the one-way clutch (5). Power is transmitted by the first speed transmission system (G1), and the engine does not blow up.

In the "R" range of the manual valve (9), the first oil passage (L
1) is connected to a sixteenth oil passage (L16) connected to the first shift valve (10 ₁ ) via a notched groove (9j) of the manual valve (9). Air release valve (15
₁ ) is closed and the second air release valve (15 ₂ ) is opened ("D").
3rd gear in “S” range) 1st shift valve (10 ₁ )
Has been switched to the second gear position on the left,
0 ₁ annular groove (10 ₁ h) No. 16 oil passage via the) (L16) is connected to the first oil chamber of the left end of the servo valve (11) (No. 17 oil passage leading to 11a) (L17), The servo valve (11) is connected to the 17th oil passage (L
17), the selector gear (4) connected to the servo valve (11) is switched to the right reverse position by the line pressure input through the line pressure input through the line pressure, and is shifted to the right reverse position. The seventeenth oil passage (L17) is connected to the eighteenth oil passage (L18) connected to the manual valve (9) via the shaft hole (11b) of the servo valve (11) connected to the oil chamber (11a).

The eighteenth oil passage (L18) is connected to the thirteenth oil passage (L13) connected to the fourth-speed hydraulic clutch (C4) via the notch groove (9c) in the "R" range of the manual valve (9). Thus, the reverse transmission system (GR) is established by refueling the four-speed hydraulic clutch (C4) and switching to the reverse side of the selector gear (6).

Set the manual valve (9) from "R" range to "D""S"
When switching to the forward range of "2", the servo valve (11)
A second oil chamber (11c) formed opposite to the first oil chamber (11a) has a nineteenth oil path (L1) branched from a fourteenth oil path (L14).
9) to input the line pressure to push the servo valve (11) to the left forward position (the position shown in the drawing). The servo valve (11) is restrained at the reverse position by the restraint means until the hydraulic pressure (hereinafter referred to as first speed pressure) of the hydraulic clutch (C1) of the transmission system (G1) becomes a predetermined value or more.

To describe this in more detail, in the present embodiment, the restraining means is
The control valve (22) is provided through an oil passage (L19), and the control valve (22) is connected to the upstream and downstream portions of the nineteenth oil passage (L19) through an annular groove (22a). The unconstrained position on the left and the constrained position on the right that cuts off this communication (the position shown)
And the oil chamber (22) at the right end of the control valve (22).
b) is connected to the third oil passage (L3) to input the first speed pressure to the oil chamber (22b), and the left end spring (22) of the control valve (22).
The spring chamber (22d) accommodating c) is connected to the seventeenth oil passage (L17), and when the manual valve (9) is switched to the "R" range, line pressure is input to the spring chamber (22d). The control valve (2
2) is reliably switched to the restraining position, and furthermore, a locking member (23) consisting of a ball to which a spring (23a) is biased
The servo valve (11) can be elastically locked between the forward position and the reverse position by the locking member (23).

According to the above configuration, in the “R” range of the manual valve (9), the control valve (22) applies the force of the spring (22 c) and the spring chamber (22).
When the manual valve (9) is switched from the "R" range to the forward range by the line pressure input to d), the control is continued until the first speed pressure rises to a predetermined value. The valve (22) is held in the restrained position and the 19th oil passage (L1
Input of line pressure to the second oil chamber (11c) of the servo valve (11) via 9) is prevented, and the servo valve (11) is held at the reverse position by the locking member (23), and then When the first speed pressure becomes equal to or higher than a predetermined value, the control valve (22) is switched to the non-constrained position against the spring (22c), and the line pressure is input to the second oil chamber (11c), and the servo valve is driven. (11) is switched to the forward position.

Thus, step on the brake and set the manual valve (9) to "R".
When switching from the range to the forward range, the servo valve (11)
When the gear is switched to the forward position, the output shaft (1b) of which the input shaft (1a) of the transmission (1) is stopped from rotating by the brake
Via a first speed transmission system (G1), the rotation of the input shaft (1a) is stopped by the engagement force of the first speed hydraulic clutch (C1), and the selector valve is switched during the switching of the servo valve (11). Gear (4) is driven gear (GRa) of reverse transmission (GR)
Input shaft (1a) even when it is in a neutral state in which it does not engage with any of the driven gear (G4a) of the four-speed transmission system (G4)
Does not rotate, and eventually the selector gear (4) and the 4-speed transmission (G
The driven gear (G4a) of 4) meshes smoothly in a state in which both the rotations are stopped, and no abnormal noise occurs due to the contact of both gears (4) (G4a).

Even if the manual valve (9) is switched from the "R" range to the forward range while the accelerator pedal is depressed to escape from mud, etc., the predetermined value of the first speed pressure at the time of switching the servo valve (11). The rotation of the output shaft (1b) in the reverse direction is stopped by the torque transmission in the forward direction via the first speed transmission system (G1) due to the ascending to the selector gear (4).
And the driven gear (G4a) of the four-speed transmission (G4) mesh with each other in a state where no large relative rotation occurs, and the two gears (4) (G4
The wear of the meshing portion of a) is prevented.

By the way, when the control valve (22) is locked at the restrained position due to the entry of foreign matter or the like, even if the manual valve (9) is switched from the "R" range to the "D" or "S" range, the servo valve (11) remains When the fourth-speed hydraulic clutch (C4) is refueled in the fourth-speed established region in this state, the reverse transmission system (GR) is established. Therefore, in this embodiment, the third shift valve ( The 20th oil passage (L) connected to the oil chamber (10 ₃ b) at the left end of 10 ₃ )
20) is connected to the upstream portion of the nineteenth oil passage (L19) through the annular groove (22e) of the control valve (22) at the restrained position of the control valve (22), and the control valve (22) is moved to the restrained position. When the manual valve (9) is switched to the "D" or "S" range in the locked state, the line pressure from the fourteenth oil passage (L14) is reduced to the twentieth oil passage (L20).
And input to the oil chamber (10 ₃ b) through the third shift valve (1
0 ₃ ), the third shift valve (10 ₃ ) is held at the third speed position to the right even if the modulator pressure is input to the oil chamber (10 ₃ a) at the right end of the fourth speed hydraulic clutch (C4 ) Can be stopped.

Also, at the reverse position of the servo valve (11), the second oil chamber (11c) of the valve (11) passes through a notch groove (11d) formed in the valve (11).
A 21st oil passage (L21) communicating with the control valve (22) is provided between the oil passage (L21) and the twentieth oil passage (L20) at an unrestricted position of the control valve (22). ), And when the control valve (22) is switched to the unconstrained position as described above by the switching operation of the manual valve (9) from the "R" range to the "D""S" range, If a delay occurs in the return operation of (22) to the forward position as described later, the line pressure is changed to the fourteenth oil passage (L14) → the nineteenth oil passage (L19) → the second oil chamber (11c) → the twenty-first oil passage.
The oil is input to the oil chamber (10 ₃ b) at the left end of the third shift valve (10 ₃ ) via the path from the oil passage (L21) to the twentieth oil passage (L20), and the third shift valve (10 ₃ ) is in the third gear position To be kept. The reason is as follows.

That is, in a transmission that performs shift control by the electronic control circuit (16), if an abnormality occurs in an input signal system such as the vehicle speed sensor (16b), normal shift control cannot be performed. The transmission may be down and cause problems such as engine overrun. In such a transmission, a self-diagnosis function for detecting an abnormality in the input signal system is added to the electronic control circuit (16). Generally, the shift control is performed so as to establish the gear. In the illustrated embodiment, the state of the fourth gear, that is, the state in which the first and second atmosphere release valves (15 ₁ ) and (15 ₂ ) are both closed is considered. Become.

Therefore, when the manual valve (9) is switched from the "R" range to the "D" or "S" range in a state where the input signal system is abnormal, the fourth speed hydraulic clutch (C4) is continuously supplied with oil. In this case, when the control valve (22) is switched to the non-restrained position, oil is supplied to the second oil chamber (11c) of the servo valve (11), and from the first oil chamber (11a) to the seventeenth oil passage (L17). The annular groove (10 ₁ h) of the first shift valve (10 ₁ ) in the second speed position
The oil is discharged to the oil discharge port (9l) through the oil passage (L16) and the cutout groove (9j) of the manual valve (9). If the oil has a high viscosity at a low temperature, the oil is discharged to the second oil chamber (11c). Oil supply from the first oil chamber (11a) is delayed, the movement of the servo valve (11) to the left forward position is delayed, and the manual valve (9) is switched to the "D" or "S" range. After that, the selector gear (4) may remain on the reverse side, and the reverse transmission system (GR) is continuously established in conjunction with refueling to the four-speed hydraulic clutch (C4), while "D" and "S" According to the switching to the range, the first-speed hydraulic clutch (C1) is also refueled, so the reverse transmission system (GR) and the first-speed transmission system (G1) are simultaneously established (C1) and (C4) clutch disc burnout. And premature wear.

However, according to the above configuration, if the movement of the forward position of the servo valve (11) is delayed, the line pressure is input to the oil chamber (10 ₃ b) at the left end of the third shift valve (10 ₃ ) as described above. Therefore, the third shift valve (10 ₃ ) is held at the third speed position on the right side, and oil is drained from the fourth speed hydraulic clutch (C4) and the third speed hydraulic clutch (C
Refueling is performed to 3), and the three-speed transmission system (G3) is established, so that the above-described problem does not occur.

Also, when switching from the "R" range to the "2" range, the return of the servo valve (11) to the forward position is delayed as described above, or the control valve (22) is locked at the restrained position, and the selector gear ( When 4) is supplied to the first-speed hold hydraulic clutch (CH) with the reverse side remaining, the first speed from the first-speed hydraulic clutch (C1) to the output shaft (1b) via the one-way clutch (5) is supplied. The output shaft (1) is transmitted via the transmission system (G1), the first-speed hold hydraulic clutch (CH), and the reverse transmission system (GR).
The path leading to b) and burning of (CH) occur. Therefore, the second
The twentieth oil passage (L20) is connected to the rightmost oil chamber (10 ₂ h) of the shift valve (10 ₂ ), and when the selector gear (4) remains on the reverse side, the oil chamber (10 2 _The line pressure was input to 2h), the second shift valve (10 ₂ ) was held at the third speed position on the left, and no oil was supplied to the first speed hold hydraulic clutch (CH).

The reason that the servo valve (11) is supplied to the servo valve (11) via the 16th oil passage (L16), the first shift valve (10 ₁ ), and the 17th oil passage (L17) in the “R” range is when the vehicle is at or above a certain vehicle speed. (When the rotation speed of the output shaft (1b) is higher than a certain value), the first shift valve (1
0 ₁ ) to the 1st gear position to prevent the connection of both oil passages (L16) and (L17), and to keep the servo valve (11) in the forward position so that the reverse transmission system (GR) is not established. According to this, when the manual valve (9) is switched from the forward range of "D""S""2" to the "R" range with the accelerator pedal depressed to escape from mud, etc. The servo valve (11 is held at the forward position, and it is possible to prevent the selector gear (4) and the driven gear (GRa) of the reverse transmission system (GR) from meshing with each other in a relatively rotated state.

In the "N" range of the manual valve (9), the first oil passage (L
It is only necessary to refuel the modulator valve (13) from 1). In the "P" range, the first oil passage (L1) is connected to the manifold valve (9).
Connected to the 16th oil passage (L16) through the notch groove (9j) of the first oil chamber (11) of the modulator valve (13) and the servo valve (11).
a) and refueling. This is because when switching from the forward range to the “P” range, the servo valve (11) is pushed to the right by refueling the first oil chamber (11a) when passing through the “R” range. This is because the position of the servo valve (11) in the "P" range changes depending on the passing speed in the "R" range, and thus the position of the servo valve (11) in the "P" range is uniquely determined as the reverse position.

In the drawing, (24) is a clutch provided to mechanically connect the input side and the output side to the fluid torque converter (3),
(25) shows a hydraulic circuit for controlling the clutch (24),
The circuit (25) has an electromagnetic third and fourth air release valve (15 ₃ ) (1
5 ₄₎ is provided, both said valve (15 ₃₎ (15 ₄₎ opening and closing control to the said electronic control circuit (16), and to control the operation of the clutch (24). The hydraulic circuit (25) is not particularly different from the one proposed by the applicant of the present invention in Japanese Patent Application No. 62-15203, and a detailed description thereof will be omitted.

(Effects of the Invention) As is apparent from the above description, according to the first aspect of the invention, the engine brake is selectively supplied to the first-speed hold hydraulic clutch and the second-speed hydraulic clutch in the low-speed holding range. A second shift used in the automatic transmission range as a shift valve that can perform traveling in the first gear stage and traveling in the second gear stage, and switches between supply and discharge of oil to and from both hydraulic clutches in the low speed holding range. Since the valve also serves as a valve, the configuration of the hydraulic circuit becomes simpler than that in which another shift valve for the low-speed holding range is provided.

According to the second aspect of the present invention, when the low-speed holding range is switched to the automatic shifting range, the oil drainage from the first-speed hold hydraulic clutch is accelerated, and the shift is performed by co-meshing the first-speed transmission system and the second-speed transmission system. The occurrence of shock can be prevented.

[Brief description of the drawings]

1 is a longitudinal sectional view of an example of a transmission to which the present invention is applied, FIG. 2 is a hydraulic circuit diagram thereof, FIG. 3 is an enlarged view of a main part of the hydraulic circuit, and FIG. 4 is a block diagram of an electronic control circuit. FIGS. 5 to 7 are diagrams showing shift characteristics in the "D" range, "S" range, and "2" range, respectively. (G1) 1st speed transmission system, (G2) 2nd speed transmission system (C1) 1st speed hydraulic clutch (C2) 2nd speed hydraulic clutch (CH) 1st speed hold hydraulic clutch (5) ... one-way clutch, (8) ... hydraulic pressure source (9) ... manual valve, (9g) ... oil drain port (10 ₁ ) ... first shift valve, (10 ₂ ) ... second shift valve ( L7)… seventh oil path (first oil path) (L8)… eighth oil path (second oil path) (L9)… ninth oil path (third oil path) (L15) …… 15th oilway (fourth oilway) (L15a) …… branchway (LD1) …… first oilway

Claims (2)

(57) [Claims] 1. A one-way clutch, comprising at least three forward transmission systems established by separate hydraulic clutches and allowing an output side over-rotation to a first-speed transmission system at the lowest speed stage, and the one-way clutch. A hydraulic circuit of a hydraulically operated transmission for a vehicle, in which a first speed hold hydraulic clutch is interposed in parallel with a manual valve that can be switched between an automatic shift range and a low speed hold range, a shift down position and a shift up position. At least two switchable first and second shift valves are provided, and the first shift valve is interposed in a first oil passage extending from the manual valve to the second shift valve. The first oil passage is communicated at the shift-up position, the communication of the first oil passage is cut off at the shift-down position of the first shift valve, and the second-speed transmission system is established. The second connected to the hydraulic clutch Connecting a passage to the first oil passage at a shift-down position of the second shift valve, and connecting the second oil passage to a third oil passage at a shift-up position of the second shift valve; When the manual valve is switched to the automatic transmission range, the first oil passage is connected to a hydraulic pressure source via the manual valve, and in a downshift position of the first shift valve, the first oil passage is arranged in series with the one-way clutch. Only the first-speed hydraulic clutch that establishes the first-speed transmission system is supplied with oil, and when the first shift valve is in the upshift position, the second shift valve is switched to the downshift position. The second-speed hydraulic clutch is supplied with oil via an oil passage, and the second-speed shift valve is switched to a shift-up position to supply a hydraulic clutch that establishes a transmission system of a higher-speed stage than the second-speed transmission system. From the second oil passage and the third oil passage The third oil passage is connected to the oil discharge passage via the manual valve in the automatic shift range of the manual valve, and the first oil pressure is discharged in the low speed holding range of the manual valve. While always supplying oil to the clutch, the supply of oil to the first oil passage is cut off, the third oil passage is switched from the drain oil passage to the hydraulic pressure source, and the shift of the second shift valve is further shifted. A hydraulic operation for a vehicle, comprising: providing a fourth oil passage connected to the third oil passage by switching to a down position, and connecting the fourth oil passage to the first-speed hold hydraulic clutch. Control device for transmission. 2. The hydraulically actuated hydraulic system according to claim 1, wherein a branch path connected to an oil discharge port of the manual valve in an automatic transmission range of the manual valve is provided in the fourth oil path. Transmission control device.